Revisão sistemática: O papel das mutações e polimorfismos genéticos na etiologia da Paralisia Cerebral.

Abstract

Cerebral Palsy is the most common motor disorder in childhood. Its prevalence in Brazil is estimated at around 30,000 to 40,000 new cases a year. The advancement in diagnostic methods in recent years has changed the profile of the PC and etiological genetic causes are considered to be an important etiology. The objective of the present study was to conduct a literature review on the latest advances in the knowledge of the genetic changes associated with the etiology of the PC. The terms Cerebral Palsy, coagulation factors, cytokines, genetic mutations, genetic polymorphisms and pediatric stroke were searched in electronic databases in order to select important publications on the subject (Medline, Scielo, PubMed, OVID, Web of Science, Elsevier Science Direct and CAPES Journals). Direct searches in the collections of the libraries of the PUC-Goiás and Federal University of Goiás also were held. Searches in databases identified 1,731 articles with potential for inclusion in the study and, after reading the summaries, 164 articles were selected for inclusion. The dates of the publications were limited from 1993 to 2013. The languages accepted for reading were Portuguese, English, French and Spanish. A large number of numeric and structural chromosomal mutations, affecting different metabolic pathways, was associated with the signs and symptoms of PC. In the studies reviewed, mutations in several genes with different functions, located on several chromosomes and with different inheritance patterns were described, highlighting the complexity of the etiology of PC. Mutations in complex AP4 (adaptor protein Complex 4), which participates in the transmembrane transport of glutamate receptor vesicles, suggest the existence of a complex AP4 syndrome, with characteristic symptoms, representing one of the few mutations with pathophysiology partially elucidated on PC. Studies correlating the PC with mutations in genes involved in the glutamate metabolism were also reviewed, which emphasizes the importance of this neurotransmitter in the PC. In the evaluated period, mutations in genes encoding factors related to the coagulation cascade, leading to hereditary thrombophilia, were the most widely studied, however, the role of these mutations on PC seems to be discreet. PC is a multifactorial and complex manifestation and different cellular mechanisms must be involved in its occurrence, reflecting various types of mutations involved in its etiology. Multicenter studies, with the largest number of individuals evaluated, are necessary in order to elucidate the complex role of genetic changes in the pathophysiology of PC.